Bicycling - Shimano Road Bike Parts Compatibility

Jan., 2018

Shimano compatibility charts come in handy for assembling your bicycle, planning purchases, or troubleshooting. We have included their compatibility and interchangeability charts from 2000 and later here as well as some other useful information and links. The Japanese Shimano site has proven the most handy as they have more charts available and it seems that their charts are more helpful than some of the English language versions we've seen. And Japanese ability isn't critical to understanding them. Just follow the lines. Comments welcome if anyone gets stuck.

For the Dura Ace 9070 Di2 11-speed grouppo: multiple shifter add-ons are available, including sprint, satellite, and time trial (TT) shifters. They simply plug into the junction box, which comes in either 3- or 5-port options. There's a new internal seatpost battery option which allows Di2 groups to keep their weight *below* the 9000 mechanical group weight. And it looks nicer. (The seatpost need not be removed to charge the internal battery).
Compatibility: Di2 7970 will not be compatible with 9070 due to the updated E-tube wiring. E-tube software is PC-only so Mac users won't be able to play as easily. Shimano PRO seatposts have become available, compatible with the internal seatpost battery. Other makers' seatposts are hitting the market as well. Because of shared technology, the 9070 Di2 uses the same E-tube wiring as 6770 Di2, so the add-on components can also be shared: satellite shifters, for example. See the cogset table for updated derailer capacity specs of new Di2.

Shimano 2013 Product Announcement

2013 Product Line

Shimano's big announcement for the 2013 model year was the 9000-series, 11-speed Dura Ace groupset.
Dura Ace Di2 9070 (2013 model) series is also announced. Compatibility of new Di2: they indicate no compatibility with 7970 or 6770 Di2 versions.
9000 series brake/brifter compatibility: Yes this component is compatible. ST-9000 shift lever, for example, can be used with BR-6700 caliper brake.
9000 series drivetrain compatibility: none. (chain, rear derailer, shifters, front derailer, crankset, cogset all show no compatibility with 10-speed models).
Though compatibility charts show no connection between the new FH-9000 rear freehub and older 10-speed components (cogsets etc.), there are indications from the Shimano news release: 11-speed hubs will be reverse compatible, via a 1.85-mm spacer, so your 10-speed cassette can be used with them. Since the 11-speed cassette is wider though, it will not fit on 10-speed hubs.

digital shifting Di2 10-speed Dura-Ace 7900 series: ST-7970; FD-7970; RD-7970 (and other shifters for time-trial etc.); digital shifting Di2 10-speed Ultegra 6700 series: ST-6770; FD-6770; RD-6770. The Ultegra versions of digital electronic shifting Di2 are available beginning with the 2012 model year. Compatibility notes: The 2012 digital shifting products are only compatible with themselves: 7970 group of 3 components should be considered as a set - no mechanical 7900 or Ultegra parts will be compatible with Dura-Ace Di2. The 6770 group will also need to be considered as a set, with no compatibility with 7900 or 7970. Shimano has said the 2 electronic groups won't be compatible due to different wiring. Also: a bit of frame compatibility may be needed: the wiring for the digital components runs through the frame and may require drilling small holes somewhere for entry and exit of these wires. Another alternative is to leave the wires outside, attached to the frame with tape. The rear derailer accommodates up to the maximum Shimano road cassette range of 11-28 teeth.

2014 Specifications manual notes that the 11-speed rear hubs FH-9000, FH-6800, FH-5800 are also compatible with 10-speed cogsets when a spacer is used.
The following Shimano hubs are compatible with 9 and 10-speed Shimano cogsets: FH-7700, FH-6500, FH-5501, FH-4400, FH-7800, FH-6600, FH-5600, FH-7900, FH-6700, FH-5700. However, it's worth referencing Sheldon's link on sprockets below to beware of a couple rare exceptions. I don't have experience with 8-speed cogsets on road bikes but they should also be compatible with the hubs listed here.

Get the latest compatibility chart from the US source directly. Shimano site charts available right here.

Shimano R700 (crankset) is the compact version of Ultegra (back in 2008). R600 is the compact version of Shimano 105.

B-level compatibility:
"Shimano says Ultegra 6700 has A-level compatibility ONLY with 6700 derailers. In an effort to offer some backward compatibility, the shifters work with both 6600-level Ultegra (and 7800-level Dura-Ace), but Shimano's terminology is B-level compatibility. It works, but it's not ideal." The dotted lines in the charts represent B-level compatibility. A real-world review of B-level compatibility is included below.

Another way they have put it: "ST-6700 levers are backwards compatible with 6600 series Ultegra drivetrains and brakes, though Shimano says mixing the groups will not take full advantage of the new features. The front derailer stroke of the new group is similar to the 6600 front derailer, but the brakes have revised pivots like Dura Ace."

Cogsets, sprockets compatibility:
For compatibility of the many rear Cogsets with Shimano drivetrains, please see the excellent compendium on the Sheldon site: Shimano Cogset Compatibility which covers many options from Shimano, IRD, Miche, SRAM, SunRace, and custom.

Di2 7970 compatibility
The electronic Di2 shifting announced in 2009 first featured Di2 7970 series. Shimano said "The new Di2 electronic group shares mechanical Dura-Ace's crankset, chain, cassette and brakes." The compatibility charts for Di2 were first released in 2015. Already, we can conclude that the 7970 series is fully compatible with the FC7900, CS7900, and CN7900. We know the Di2 derailers are all short cage only - they have no compatibiility with triple cranks. When electronic Ultegra was released, it was indicated that 7970 and 6770 would be incompatible due to different wiring.

Di2 9070 compatibility
As with 7970 series, Shimano's statement "The new Di2 electronic group shares mechanical Dura-Ace's crankset, chain, cassette and brakes" holds with the 9070 series as well. These components are compatible with FC9000, CS9000, CN9000, and BR9000 (with only the shifter compatibility with brake calipers shown in the '13 and '14 charts). We know there's no backward compatibility with Dura Ace 7970 due to differences in wiring. Read the next section for comments about compatibility with the 6770 and 6870 series.

Di2 Ultegra - 6770 and 6870 - compatibility
The first comment to make about Ultegra Di2 is just Shimano's original statement, which is expected if not obvious: "The new Di2 electronic group shares [the mechanical group]'s crankset, chain, cassette and brakes". This holds for the Ultegra 6770 and 6870 series as well. Shimano has kept the charts simple by excluding the Di2 components. But what about compatibility among the Di2 groups? (Added in 2015 - See Di2 Compatibility Page). There's no backward compatibility with Dura Ace 7970 due to differences in wiring. The other groups, after 7970, share the same wiring. There are user sites in Japan as well as other places assuring that there are no issues between, say, ST6770 and RD9070, or between ST6770 and FD6870. On the other hand, the 9070 upgrade kit claims it cannot be used to convert 10-speed groups as the chainring, chain, and cassette would all be mismatched.
Regarding remote sprinter shifter for Di2: product SW-R610 (remote sprinter shifter) is compatible with ST6870. However, it cannot be used with ST6770 "because the shape of its connector is different from that of the E-tube." The remote sprint shifter can of course also be used with ST9070 (Dura Ace).

Triple Crank and compatibility:
See the 2011 front drivetrain compatibility chart above for some details. The left (front) shifter, the crankset, and both derailers may be specific for a triple gearling. If you have a 105 front brifter, you may be lucky as it's non-indexed so the same brifter can be used with a double or a triple. If yours is Ultegra, there should be a difference so you need the specific front brifter for double or triple whether you're on the 6600 or 6700 series. The front derailer has much different spacing on a triple crankset. And the rear derailer has a long cage to collect more chain - so both of these are specific for triple gearing. Another thing that many people don't realize - the new Shimano chains are *not* triple-compatible. (As indicated on the 2011 compatibility chart), The reason for this is that the new chains (CN-7901, 6701, or 5701) do not allow enough lateral movement. So for the moment, your triple chain needs should be satisfied by KMC, by SRAM, Wippermann maybe, or by the older Shimano chains (CN-7801, CN-6600, CN-5600).

Brake Shoes and Pads
R55C3 is the model number for the Shimano branded spare brake pads (2011). It comes in different compounds for alloy (aluminum) and carbon rims. The pad length is 55mm and this pad is compatible with BR-7900, BR-7800, BR-7700, BR-6700, BR-6600, BR-6500, BR-5700, BR-5600, BR-5501, BR-5500, BR-R650, BR-R600, BR-R561 calipers. R55C3 replaces the R55C model which used the same specification but slightly different compounds. Kool Stop has for many years marketed fully compatible replacement pads in a few different compounds. Swiss Stop markets high-performance pads which are also compatible. There are also a few other vendors. R55C4 is the model number for the Shimano branded pads for the 11-speed sets from 2014: BR-9000, BR-6800, BR-6810, BR-9010 are designed to use R55C4.

Brake Calipers and Tire Sizes
According to Specifications (Aug 2014), maximum tire sizes for Shimano road calipers are given as follows: Models BR-9000, BR-9010, and BR-6800 allow up to 25mm tires; models BR-6810, BR-5810, and BR-5800 allow up to 28mm tires. No other guidance for older caliper models was provided.

FC5603 crank limitation
For compatibility with front derailer FD5603, the FC5603 Shimano 105 crank should use chainrings of 50-39-30 tooth sizes. This is in Shimano charts for Front Drivetrain, 2008 and 2009. This likely indicates a limitation in the front derailer capacity, but I don't know why the Ultegra FD6603, which has capacity for the standard 52-39-30 tooth ringed Ultegra triple crank, would not also support the smaller toothed 105 crankset. There is no compatibility shown for this combination in any of the charts.

Rear derailer capacity limits
For Details, see derailer capacity table.
Shimano charts provide for an exception to the compatibility rules between cassette sprockets and rear derailers. Specifically, only the 7900-, 6700-, and 5700- series rear derailers have sufficient capacity to support a cassette with sprockets differing as much as 16 teeth or more from small to large cog. For this reason, the 11-28 tooth cogset (17 tooth difference), available in 7900-, 6700-, and 5700- series is not compatible with the older series rear derailers. The 11-27 tooth cogset has the same limitation. For the older 10-speed derailers (7800-, 6600-, and 5600-series), the maximum cogset tooth size difference supported is up to 15 teeth (as in the 12-27 size). In the 2012-2015 model years, the available products and their limits have seen some additions and special cases. These details are being tracked in the derailer capacity table. You can also
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Junior sprockets with 13 or more toothed top gear
A difference exists in cassette sprockets labeled CS-6600 which are for "junior gearing". Do not use the "junior gearing" CS-6600 sprockets with normal freehubs - they do not fit. Junior gearing CS-6600 sprockets can be identified as having a top gear of 13, 14, 15, or 16 teeth. The normal size sprockets, which are compatible with all normal freehubs, can be identified as having a top gear of 12 or 11 teeth.
Another important difference exists with the junior sprockets: their spacer requirements differ. Riders planning to try one of the sprockets with top gear 13 or more teeth - research this part carefully. Other riders can safely follow the compatibility charts for your planning.
Finally, do not use one of these junior sprockets with a triple front chainwheel -that combination is not compatible.
Details on Junior sprocket compatibility have been provided in a link from the 2006 compatibility page.

Part Naming Color Codes
Shimano parts such as FC-6601 may have a 1-letter suffix, for example FC-6601-G. This letter is a color indicator and for the purposes of compatibility, this letter is ignored. The monkey can sleep easier without it, knowing the color does not affect compatibility in any part combination. Use the charts and the monkey without the color suffix. Other suffixes were for example, RD-5600-S (silver), ST-5600-L (black), where the FC-6601-G is gray. Parts with no suffix are silver, as is the suffix S, only used when there is another color option for the same part.

Brake and Shift CablesDerailer: For best results always replace the cables when upgrading any drivetrain part. In 2010, Shimano introduced colored cable housing options whereas previously only "Dura Ace Gray" was available. The SP41 PTFE cableset is standard replacement derailer cable and housings for the Shimano 7900 Dura-Ace system. Compatible with all 7- through 10-speed Shimano road shifter/derailer sets as well as SRAM. Shimano's 7900 shift cable/housing set is ideal for the Dura-Ace 7900, Ultegra 6700, and 105 5700 STI levers with cable routing under the bar tape. In fact, it was because of the under-the-bar-tape cable positioning change first designed for Dura Ace 7900 that the PTFE-lubricated housing was introduced. PTFE (better known as DuPont Teflon) coated cables do a good job of minimizing friction and greatly enhance shifting performance. The engineers at Shimano have spent countless hours researching and developing shift cables and housing that will optimize the performance of their shifters and derailleurs. The PTFE(Teflon) coated derailer cable set is the most advanced they have ever produced. A complete set of cable and housing for Shimano derailers (enough for one road bicycle) features 4mm SIS-SP41 housing; Choose your color; Weight: 160 grams (reported); Cable Diameter: 1.2 mm; Cable Lengths: 2 x 2000 mm; Stainless steel cable for long life in all conditions. (Tip: Use the "gray" Dura Ace pack to get all end caps and ferrules to complete the job - the blue pack has been reported to contain fewer of these).
Brakes:
The 7900 Dura-Ace brake cable set has been optimized for Shimano levers but makes a great upgrade for most road systems. New super low friction PTFE coated cables virtually eliminate excess friction for top performance. The brake cable end fits road bike levers only. A complete set of cable and housing for Shimano brakes (enough for one road bicycle) features 1400mm x 5mm housing x 1; 800mm x 5mm housing x 1; 2050mm x 1.6mm cable x 1; 1000mm x 1.6mm cable x 1; PTFE coated stainless steel cable for long life in all conditions; two cable crimps, and two ferrules. 178 grams (reported).

Computers
The Shimano Flight Deck SC-6502 Computer head features the following: gearing and wheel size data for four bikes can be programmed and accessed from one computer head. Program one, two, or three chainrings; display shows the number of chainrings programmed. Gear size display: once shift is made, computer will momentarily show what chainring/gear combination bike is in, 53-12 etc. One button on each brake lever controls computer function.
Bracket and sensor kit sold separately. Compatible with compact road gearing.
Compatibility: The Flight Deck SC-6502 computer will work with STI levers ST-7800, ST-7900, ST-6600, ST-6603, ST-6700, ST-6703, and ST-5600. It is not compatible with brifters ST-5700 or ST-5703. As of 2014 (August), the Flight Deck computer is not compatible with the newer 11-speed brifters (ST-9000, ST-6800, ST-5800, per Shimano specifications. Use the wireless harness for all of the 10-speed brifters and the SC-6502. (10-speed Harness is ID SM-SC70) The wireless harness isn't completely wireless though. There are still wires that run from the STI levers to the computer (underneath the handlebar tape). But there is no wire running down the fork to the pickup.
The older SC-6501 Flight Deck will work with most 9-speed Shimano brifters. (ST-7700, ST-6510, ST-5500) Source: Shimano Tech Docs.
The Flight Deck computer is quite interesting. You pre-configure the computer to know what gears you have; whether the cassette is a 12-25 or a 11-23, for instance. The STI levers tell the computer what gear you're in. So, the computer always knows your gear ratio. From that, and from the wheel pickup, it knows how fast you're riding. And since it knows your speed and your gear, it can calculate your cadence. (The odd "feature" with this is the virtual cadence: it does not know whether you are pedaling at all, so on your downhill coasts, you will see a cadence value well over 100 when you're not even pedaling)

Shimano 105 Triple Shifter Change
The 9-speed 105 front (left) shifter (model ST-5500 or ST-5510) is compatible with both a double or a triple crank configuration. Shimano's move to 10-speed cogsets initially started out like this: the 105 front shifter (left, ST-5600) was compatible with both a double or a triple crank configuration. But Shimano saw a large number of warranty claims due to breakage of the shifters caused by improper setup early on. Their response was to introduce the double-only compatible ST-5601 and the triple-only ST-5603. Ultegra and Dura-Ace already had the double-only and triple-only shifters.
So, an ST-5601 left shifter is the only one of the 10-speed 105s which is not compatible with triple cranksets. ST-5600 or ST-5603 are good for triples, and ST-5600 is actually a little more prone to damage when setup for double cranks.

2012 Rear Derailer low gearing options
The 2012 Shimano compatibility chart (Rear section) shows the RD5700 and RD5700A. The differences between these boxes relates to the cogset support - specifically, the size of the largest cog supported. The RD5700, like its Ultegra and Dura Ace counterparts shown, can be used when your cogset has a large cog of 21 to 28 teeth. The RD5700A shown in the lower box with a Tiagra model, can be used in combination with a large cog of 25 to 30 teeth. Shimano began in 2012 to provide greater support for hill-climbing (low) gearing in double and compact-double configurations, possibly with an eye to phasing out triples in the future. With the market moving to 11 speed cogsets, this may make sense on road bikes. Refer to the Shimano Compatibility Tables on this site for notes on Derailer Capacity, which affects cogset compatibility.

2013 Rear Derailer low gearing options
The 2013 Compatibility Chart (Rear section) shows in separate boxes the RD6700A (Ultegra) and the RD5701 (105). As noted, these differences relate to the cogset support - specifically, the size of the largest cog supported. The RD6700A can be used with a large cog of 23 to 30 teeth, while the RD5701 shown in the lower box with a Tiagra model, can be used with a large cog of 25 to 32 teeth. Shimano began in 2012 to provide greater support for low gearing in double and compact-double configurations. Refer to the Shimano Compatibility Tables on this site for notes on Derailer Capacity, which affects cogset compatibility.

2014-15 Rear Derailer low gearing options
The 2014 and 2015 Compatibility Charts (Rear section) showsa lot of gearing options in separate boxes. Starting with 11-speed models, RD6800 and 5800 come in SS (short cage) and GS (medium cage) now. And on the 10-speed models, the RD6700A and RD5701 are separated. As noted, these differences relate to the cogset compatibility - specifically, the size of the largest cog that will work. The RD6800SS can be used with a large cog of 23 to 28 teeth, while the RD6800GS can be used with a large cog of 28 to 32 teeth. Shimano began in 2012 to provide greater support for low gearing in double and compact-double configurations, possibly with an eye to phasing out triples in the future. Refer to the Shimano Compatibility Tables on this site for notes on Derailer Capacity, which affects cogset compatibility.

Rear Derailer Naming and Charts
Most of the Shimano charts leave off mention of triple rear derailers, but there are important distinctions to be aware of. For the monkey and these note pages, we use the standard "03" naming convention for triple rear derailers. There are actually several possible naming conventions for rear derailers, and it is important to distinguish them. The triple-compatible rear derailers, designated on this site as RD-6603 and other IDs ending in "03" (possibly "04"), have a longer cage to be able to take up more chain, as triples run longer chains than doubles. In other places, and some of Shimano's later charts, these triple rear derailers are designated "GS" as in "RD-6600-GS". These are the same thing. One other description you will hear is "long cage" or "medium cage" to refer to road triples. On a road bike, it's considered long since it's longer than a short-cage RD used for doubles. But since there exist even longer cages (on MTBs for example), the road triple RDs are also called "medium cage" sometimes.
Double Derailers: These are designated here as ending in "00" or "01". Other places use "RD-6600-SS" and other IDs suffixed with "SS", or possibly "RD-6600" short cage. There is little difference in functionality among RDs, so the Monkey learned to assume compatibility with respect to triple RDs as parallel to double RDs.

Rear Derailer Capacity Note
The rear drivetrain compatibility Chart of 2017 points out the following guidance for rear derailers: RD-R9100 and RD-R9150 compatibility is confirmed for use with a cassette sprocket of 25 to 30 teeth (low, inclusive). RD-5800-GS, RD-6870-GS, and RD-6800-GS should be used with a cassette sprocket of 28 to 32 teeth. RD-9000, RD-6800-SS, RD-5800-SS should be used with a cassette sprocket of 23 to 28 teeth (low, inclusive).
With 10-speed sprockets, the guidance is this: RD-6700A (models short cage and long cage): use with 23-30 tooth cassette; RD-5701, RD-4601: use with 25-30 tooth cassette; RD-5703, RD-4603 (aka RD-5701-GS and RD-4601-GS aka long cage): use with 27-32 tooth cassette (low gear) for double configuration, use with 25-30 tooth cassettes for triple configurations; RD-R350-10: use with 30-34 tooth cassette; RD-4703 (aka RD-4700-GS): use with 25-32 tooth low cassette sprocket.

Tip: for triple rear derailers, look for "GS" or "long cage" (sometimes aka "medium cage") or the "03" or "04" numbers. For double rear derailers, look for "SS" or "short cage" or the "00" or "01" numbers. (example: RD-6600-GS is long cage)

Shimano Chain compatibility:
Generally, chains tend to be compatible between SRAM and Shimano as long as they are of equal gearing. Purist mechanics, though, have been known to suggest Shimano-only for the latest 10-speed models (5701 105 chain with Shimano's 5700, 6700, and 7900-series groupsets for example). This point is debated, but if you want the no-debate solution, run the Shimano chains with your system (they're not that expensive fortunately). 10-speed chains won't work well with 9-speed mech and vice versa. Also, Wippermann and KMC provide chains compatible with Shimano. The 7900/6700/5700 series chains are not compatible with triple cranksets (see note above), and SRAM and KMC may fall into the same category as 7800 chains with respect to compatibility with 7900-series parts (see charts). And chains in these series will wear slightly less on the rear sprockets (when installed correctly) due to the asymmetry - outer link plates being a bit shaped for shifting. Wippermann provides an excellent joining pin which works pretty well with Shimano chains (but again purist mechanics have been known to debate this point for very slight irregularities observed). For 10-speeds, the KMC joining pin is also great, and with 9-speeds, the KMC or SRAM joining pins will work well with Shimano chains. The Shimano joining pin system requires a chain tool and is quite a bit harder to work with than any of the others.

SRAM derailer/shifter sets are compatible with Shimano chains and cassettes (however be consistent with shifter / derailer choices. SRAM shifter and derailers can be used with Shimano chains, cassettes. They may not be optimal however, probably what Shimano calls "B-level" compatibility.

For best results, replace the cables when upgrading any drivetrain part.

Mixing a non-Shimano crank or chain into a Shimano Di2 component group has resulted in crashes and destroyed derailleurs. Only the all-Shimano componentry will enable the repair to be covered by warranty.

The following is one rider's Summary of upgrading a bike to ST-6700 shifters from ST-6600.
(this combination is dotted-line B-level compatible in Shimano's 2010 charts). This should give an illustration of "B-level compatibility" concept in practice.

"Shifting (Ultegra 6700 shifters with Ultegra 6600/Dura-Ace 7800 derailleurs):
The actual shifting is perfect. However, the FEEL of the shifters is not quite the same.
The front (left) shifting from small to large chainrings is probably better. The Ultegra 6700 shifter retains the feather/trim position like the ST-6600."

"However, my opinion is that the FEEL of the back (right) shifter is less positive than the 6600. As before, the actual shifting quality (accuracy, quickness, etc.) is unchanged." But the reviewer preferred the feel of the ST-6600 shifter when paired with the Dura-Ace RD-7800 Rear Derailer.

"Braking (Ultegra 6700 shifters with DA 7800 brakes):
The difference in pull ratio is noticeable. Braking is inferior with this combo compared to Ultegra ST-6600 with Dura Ace BR-7800 brake calipers. Still, braking performance is fine. Braking, however, is definitely more comfortable with the new shifters with the pivot being relocated higher up."

From a bike shop:
"we just had a bike in for a service today that had one 5600 lever paired with a 5700 brake. It was the first time I'd got to try this combination, and I immediately found out that the braking sucked on the test ride ... I was surprised by how pathetic and mushy it felt."
"So stick with components of the same series unless you have no choice."
"BTW, going the other way (e.g. new 6700 levers with old 6600 brakes) can be made to work OK - just setup the brake so that it doesn't hit the rim until the lever has moved a little more than normal, but still far from the bars, and you get reasonably decent power and modulation. The cable pull ratio actually changes during the lever sweep with the new levers, which I believe Shimano call Servo Wave technology, which is why it matters where the bite point of the brake is."

SRAM RED with the Ultegra FD:
"It works perfectly.
I've been having trouble with SRAM front shifting. I thought it was the Red FD, so I went and bought a Force FD. That didn't help much at all. I set both up exactly as I was supposed to, but it just didn't want to work. I tweaked this and tweaked that, but in the end there is a very limited range of adjustment that a FD can have... It's not rocket science, but for some reason I couldn't get reliable shifting with either the Red or Force FDs. I wasn't dropping the chain, but there was simply too much hesitation and grinding before the chain actually caught."
"Then I installed the Ultegra FD...in one try. That's all it took for superb shifting. I couldn't be happier with the performance... It's not quite as solid shifting as the full 6700 group was when I had it on my bike, but it's more than good enough."

105 9-speed derailer replacement:
"It depends on whether or not you have indexed shifting. If you have indexed shifting only a 9-speed rear derailer will work regardless of claims."
"9 speed to 10-speed compatibility in rear derailers only applies for non-indexed shifting. [sources: Shimano Reps, a mechanical engineer]. Your only options are as follows: locate a true Shimano 105 9-speed derailer (RD-5500); purchase a 9-speed Tiagra rear derailer (includes 2010 and 2011 models); or upgrade to a 105 10-speed drivetrain."
"Since I have replaced the derailer with a true 9-speed Tiagra derailer (2011 RD-4500), the shifting problems are gone. I also measured the derailer movement / shift and it matches the cassette cog spacing."
For a triple, the Tiagra RD4500-GS 9-speed (2011) is the way to go.